<VV> Verdict on: Bad Idle (66 140)

N. Joseph Potts pottsf@msn.com
Sat, 14 Aug 2004 13:25:23 -0400

I performed a leakdown test (ear gauge), and found leakage from #4 through
the intake. I pulled the head off.
     The VALVE GUIDE on that intake valve, which had been resleeved with
bronze, had broken, evidently near the end that's in the combustion chamber.
I am missing that inch, more or less, from that end of the guide (which
pulled out of the head by hand). This head had been professionally
refurbished in May 2003, and installed in February 2004. Less than 5,000
miles. Teflon valve-stem seals were installed then. There is no evidence
that the valve seat came out. The cylinder had good compression before the
valve guide broke; after that, it still had compression, but only 102psi. I
think effective (rather than test) compression may have been worse than
     I find metal from the guide in all three cylinders, but I'm hoping most
of it got there during leakdown testing, rather than during driving. I'll be
doing a thorough cleanup on the pistons/cylinders and putting on another
(fresh) head.
     Thanks to all who responded to my initial post with subject as above.

Joe Potts
Miami, Florida USA
1966 Corsa coupe 140hp 4-speed with A/C